/*
 * Copyright 2016 Google Inc. All Rights Reserved.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

var Util = window.Util || {};

Util.isDataURI = function(src) {
  return src && src.indexOf('data:') == 0;
};

Util.generateUUID = function() {
  function s4() {
    return Math.floor((1 + Math.random()) * 0x10000)
    .toString(16)
    .substring(1);
  }
  return s4() + s4() + '-' + s4() + '-' + s4() + '-' +
    s4() + '-' + s4() + s4() + s4();
};

Util.isMobile = function() {
  var check = false;
  (function(a){if(/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|mobile.+firefox|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows ce|xda|xiino/i.test(a)||/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i.test(a.substr(0,4)))check = true})(navigator.userAgent||navigator.vendor||window.opera);
  return check;
};

Util.isIOS = function() {
  return /(iPad|iPhone|iPod)/g.test(navigator.userAgent);
};

Util.isSafari = function() {
  return /^((?!chrome|android).)*safari/i.test(navigator.userAgent);
};

Util.cloneObject = function(obj) {
  var out = {};
  for (key in obj) {
    out[key] = obj[key];
  }
  return out;
};

Util.hashCode = function(s) {
  return s.split("").reduce(function(a,b){a=((a<<5)-a)+b.charCodeAt(0);return a&a},0);
};

Util.loadTrackSrc = function(context, src, callback, opt_progressCallback) {
  var request = new XMLHttpRequest();
  request.open('GET', src, true);
  request.responseType = 'arraybuffer';

  // Decode asynchronously.
  request.onload = function() {
    context.decodeAudioData(request.response, function(buffer) {
      callback(buffer);
    }, function(e) {
      console.error(e);
    });
  };
  if (opt_progressCallback) {
    request.onprogress = function(e) {
      var percent = e.loaded / e.total;
      opt_progressCallback(percent);
    };
  }
  request.send();
};

Util.isPow2 = function(n) {
  return (n & (n - 1)) == 0;
};

Util.capitalize = function(s) {
  return s.charAt(0).toUpperCase() + s.slice(1);
};

Util.isIFrame = function() {
  try {
    return window.self !== window.top;
  } catch (e) {
    return true;
  }
};

// From http://goo.gl/4WX3tg
Util.getQueryParameter = function(name) {
  name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");
  var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
      results = regex.exec(location.search);
  return results === null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
};


// From http://stackoverflow.com/questions/11871077/proper-way-to-detect-webgl-support.
Util.isWebGLEnabled = function() {
  var canvas = document.createElement('canvas');
  try { gl = canvas.getContext("webgl"); }
  catch (x) { gl = null; }

  if (gl == null) {
    try { gl = canvas.getContext("experimental-webgl"); experimental = true; }
    catch (x) { gl = null; }
  }
  return !!gl;
};

Util.clone = function(obj) {
  return JSON.parse(JSON.stringify(obj));
};

// From http://stackoverflow.com/questions/10140604/fastest-hypotenuse-in-javascript
Util.hypot = Math.hypot || function(x, y) {
  return Math.sqrt(x*x + y*y);
};

// From http://stackoverflow.com/a/17447718/693934
Util.isIE11 = function() {
  return navigator.userAgent.match(/Trident/);
};

Util.getRectCenter = function(rect) {
  return new THREE.Vector2(rect.x + rect.width/2, rect.y + rect.height/2);
};

Util.getScreenWidth = function() {
  return Math.max(window.screen.width, window.screen.height) *
      window.devicePixelRatio;
};

Util.getScreenHeight = function() {
  return Math.min(window.screen.width, window.screen.height) *
      window.devicePixelRatio;
};

Util.isIOS9OrLess = function() {
  if (!Util.isIOS()) {
    return false;
  }
  var re = /(iPhone|iPad|iPod) OS ([\d_]+)/;
  var iOSVersion = navigator.userAgent.match(re);
  if (!iOSVersion) {
    return false;
  }
  // Get the last group.
  var versionString = iOSVersion[iOSVersion.length - 1];
  var majorVersion = parseFloat(versionString);
  return majorVersion <= 9;
};

Util.getExtension = function(url) {
  return url.split('.').pop().split('?')[0];
};

Util.createGetParams = function(params) {
  var out = '?';
  for (var k in params) {
    var paramString = k + '=' + params[k] + '&';
    out += paramString;
  }
  // Remove the trailing ampersand.
  out.substring(0, params.length - 2);
  return out;
};

Util.sendParentMessage = function(message) {
  if (window.parent) {
    parent.postMessage(message, '*');
  }
};

Util.parseBoolean = function(value) {
  if (value == 'false' || value == 0) {
    return false;
  } else if (value == 'true' || value == 1) {
    return true;
  } else {
    return !!value;
  }
};

/**
 * @param base {String} An absolute directory root.
 * @param relative {String} A relative path.
 *
 * @returns {String} An absolute path corresponding to the rootPath.
 *
 * From http://stackoverflow.com/a/14780463/693934.
 */
Util.relativeToAbsolutePath = function(base, relative) {
  var stack = base.split('/');
  var parts = relative.split('/');
  for (var i = 0; i < parts.length; i++) {
    if (parts[i] == '.') {
      continue;
    }
    if (parts[i] == '..') {
      stack.pop();
    } else {
      stack.push(parts[i]);
    }
  }
  return stack.join('/');
};

/**
 * @return {Boolean} True iff the specified path is an absolute path.
 */
Util.isPathAbsolute = function(path) {
  return ! /^(?:\/|[a-z]+:\/\/)/.test(path);
}

Util.isEmptyObject = function(obj) {
  return Object.getOwnPropertyNames(obj).length == 0;
};

Util.isDebug = function() {
  return Util.parseBoolean(Util.getQueryParameter('debug'));
};

Util.getCurrentScript = function() {
  // Note: in IE11, document.currentScript doesn't work, so we fall back to this
  // hack, taken from https://goo.gl/TpExuH.
  if (!document.currentScript) {
    console.warn('This browser does not support document.currentScript. Trying fallback.');
  }
  return document.currentScript || document.scripts[document.scripts.length - 1];
}


module.exports = Util;
